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Öğe Effect of carnitine on the swimming endurance time in rats(Aves, 2007) Guituk, Seth; Demirkazik, Ayse; Erdal, Sena; Demir, TuncerPurpose: Carnitine plays an important role in lipid metabolism by transporting long-chain fatty acids into the mitochondria for beta-oxidation. The effect of carnitine on exercise capacity is not clear. In this study, effect of carnitine on endurance time in swimming exercise was evaluated in rats. Material and Methods: Two groups were formed and a total of 20 Wistar albino male rats weighing 250-300 g were used in this study. Each rat of experiment group (n = 10) subcutaneous injection of carnitine at the dose of 100 mg/kg/day was made for 20 days, while placebo was given in control group (n = 10). Swimming tests was made in a square shaped glass water tank that was 50 centimeters in height, in width, in depth and filled to a depth of 40 centimeters with 25 +/- 1 degrees C water. The uncoordinated movements and staying under the water for 10 seconds without swimming at the surface were accepted as the exhaustion criteria of the rats. Results: In the rats of experiment group the endurance time increased significantly comparing with the control group (p < 0.05). Conclusion: This result suggests that carnitine may enhance the physical performance. Carnitine might generate that effect by induction of maximal oxygen intake and/or mitocondrial Ca++ sequestration.Öğe Effect of Exposure to 50 Hz Magnetic Field With or Without Insulin on Blood Brain Barrier Permeability in Streptozotocin-Induced Diabetic Rats(WILEY, 2010) Gulturk, Sefa; Demirkazik, Ayse; Kosar, Ilkay; Cetin, Ali; Dokmetas, Hatice S.; Demir, TuncerWe investigated the effect of long-term exposure to modulation magnetic field (MF), insulin, and their combination on blood brain barrier (BBB) permeability in a diabetic rat model. Fifty-three rats were randomly assigned to one of six groups: sham, exposed to no MF; MF, exposed to MF; diabetes mellitus (DM), DM induced with streptozotocin (STZ); DM plus MF (DMMF); DM plus insulin therapy (DMI); and DM plus insulin therapy plus MF (DMIMF). All the rats underwent Evans blue (EB) measurement to evaluate the BBB 30 days after the beginning of experiments. The rats in MF, DMMF, and DMIMF groups were exposed to MF (B = 5 mT) for 165 min every day for 30 days. Mean arterial blood pressure (MABP), body mass, and serum glucose level of the study rats were recorded. The extravasation of brain EB of the MF, DM, DMMF, DMI, and DMIMF groups was higher than that of the sham group and the extravasation of right hemisphere of the DMIMF group was highest (P < 0.05). The post-procedure body mass of the sham and MF groups were significantly higher than those of the DM and DMMF groups (P < 0.05). In the DM, DMMF, DMI, and DMIMF groups, the baseline glucose was significantly lower than the post-procedure glucose (P < 0.05). DM and MF increase BBB permeability; in combination, they cause more increase in BBB permeability, and insulin decreases their effect on BBB. Improved glucose metabolism may prevent body mass loss and the hypoglycemic effect of MF. DM increases MABP but MF causes no additional effect. Bioelectromagnetics 31:262-269, 2010. (C) 2009 Wiley-Liss, Inc.Öğe Evaluation of effects of T and N type calcium channel blockers on the electroencephalogram recordings in Wistar Albino Glaxo/Rij rats, an absence epilepsy model(MEDKNOW PUBLICATIONS & MEDIA PVT LTD, 2015) Durmus, Nedim; Gulturk, Sefa; Kaya, Tijen; Demir, Tuncer; Parlak, Mesut; Altun, AhmetObjectives: It is suggested that excessive calcium entry into neurons is the main triggering event in the initiation of epileptic discharges. We aimed to investigate the role of T and N type calcium channels in absence epilepsy experimental model. Materials and Methods: Wistar Albino Glaxo/Rij (WAG/Rij) rats (12-16 weeks old) were randomly allocated into four groups; sham, mibefradil (T type calcium channel blocker), w-Conotoxin MVIIA (N type calcium channel blocker), and mibefradil w-Conotoxin MVIIA. Beta, alpha, theta, and delta wave ratios of EEG recordings and frequency and duration of spike wave discharges (SWDs) were analyzed and compared between groups. Results: Beta and delta recording ratios in 1 M/5 l mibefradil group was significantly different from basal and other dose-injected groups. Beta, alpha, and theta recordings in 0.2 M/5 l w-Conotoxin MVIIA group was significantly different from basal and other dose-injected groups. In w-Conotoxin MVIIA after mibefradil group, beta, alpha, and theta recording ratios were significantly different from basal and mibefradil group. Mibefradil and w-Conotoxin MVIIA significantly decreased the frequency and duration of SWDs. The decrease of frequency and duration of SWDs in mibefradil group was significantly different from w-Conotoxin MVIIA group. The frequency and duration of SWDs significantly decreased in w-Conotoxin MVIIA after mibefradil group compared with basal, mibefradil, and w-Conotoxin MVIIA groups. Conclusions: We concluded that both T and L type calcium channels play activator roles in SWDs and have positive effects on frequency and duration of these discharges. These results are related with their central effects more than peripheral effects.Öğe Febril konvulsiyonlu sıçanlarda manyetik alanın kan-beyin bariyeri ve beyin dalgaları üzerine etkisi(Cumhuriyet Üniversitesi, 2009) Demir, Tuncer; Gültürk, SefaManyetik alanın (MA) çocukluk döneminin febril konvulsiyonu (FK) nasıl etkilediği bilinmemektedir. Manyetik alanın FK nöbet latansı ve süresi, kan-beyin bariyeri (KBB), beyin dalgaları ve hipokampus üzerine etkilerini incelemeyi amaçladık.Çalışmada, toplam 72 adet 21 günlük olan Wistar Albino erkek sıçan kullanılmıştır. Çalışmamız 6 gruptan oluşmuştur: S; sham grubu, FK; febril konvulsiyon, MA; manyetik alan, FK+MA; FK sonrası MA, MA+FK; FK öncesi MA, MA+FK+MA; FK öncesi ve sonrası MA uygulanan grup. Tüm gruplarda KBB, nöbet latansı ve süresi, elektroensefalografi kayıtları, ortalama arteryel kan basınçları (MABP), rektal ısıları, serum elektrolitleri ve immunhistokimya boyamaları yapılmıştır.FK gruplarının son MABP değerleri S ve MA gruplarının son değerlerine göre yüksekti (p<0.05). MA+FK+MA grubunun serebellum, sağ hemisfer, sol hemisfer EB değerleri en yüksekti (p<0.05). FK, MA, FK+MA, MA+FK ve MA+FK+MA gruplarının serebellum EB değerleri sham grubundan anlamlı olarak yüksek bulundu (p<0.05). FK geçiren grupların son nöbet latansları ilk latanslardan düşüktü (p<0.05). MA uygulanan FK gruplarının nöbet süreleri MA uygulanmayan gruplara göre anlamlı olarak düşüktü (p<0.05). MA uygulaması beta power oranını azaltırken alfa, teta ve delta power oranlarını artırdı (p<0.05). FK ve/veya MA uygulaması VEGF ekspresyonunu artırdığı gözlendi (p<0.05).Febril konvulsiyonlu sıçanlarda MA uygulaması, süreyle orantılı olarak KBB'ni bozmuştur ve bu etki en fazla serebellumda gözlenmiştir. FK ve/veya MA uygulanması MABP'yi artırmıştır. KBB bozulması, kan basıncı artışından kaynaklanabilir. MA, FK nöbet süresini kısaltırken latansı etkilememiştir. MA uygulaması FK'lı sıçanların beyin dalgalarını olumsuz yönde etkilemiştir. Sonuç olarak, MA uygulaması, KBB'ni bozarak hipokampal nöronlarda hasarlanmaya neden olmasına rağmen febril konvulsiyon nöbet süresini kısaltmıştır.Anahtar sözcükler: Febril konvulsiyon, Manyetik alan, Kan-beyin bariyeri, EEG, Nöbet süresi
